Carbon Nanotubes & Graphene
Unzipped nanotubes unlock potential for batteries
June 13, 2013 4:04 pm | News | CommentsResearchers at Rice Univ. have come up with a new way to boost the efficiency of the ubiquitous lithium-ion battery by employing ribbons of graphene that start as carbon nanotubes. Proof-of-concept anodes built with graphene nanoribbons and tin oxide showed an initial capacity better than the theoretical capacity of tin oxide alone.
Controlling magnetic clouds in graphene
June 12, 2013 8:14 am | News | CommentsWonder material graphene can be made magnetic, and its magnetism can be switched on and off at the press of a button. This opens a new avenue towards electronics with very low energy consumption. In a report published by a Univ. of Manchester team shows how to create elementary magnetic moments in graphene and then switch them on and off. This is the first time magnetism itself has been toggled.
Halogenated graphene may replace platinum in low-cost fuel cells
June 10, 2013 10:56 am | News | CommentsThe research team of Ulsan National Institute of Science and Technology paved a new way to affordable fuel cells with efficient metal-free electrocatalysts using edge-halogenated graphene nanoplatelets. The research team, for the first time, reportedly synthesized a series of edge-selectively halogenated graphene nanoplatelets by ball-milling graphite flake in the presence of chlorine, bromine or iodine, respectively.
Even with defects, graphene is strongest material in the world
May 31, 2013 1:57 pm | News | CommentsIn a recently published study, Columbia University researchers have demonstrated that graphene, even if stitched together from many small crystalline grains, is almost as strong as graphene in its perfect crystalline form. This work resolves a contradiction between theoretical simulations, which predicted that grain boundaries can be strong, and earlier experiments, which indicated that they were much weaker than the perfect lattice.
Invention allows clear photos in dim light
May 30, 2013 8:06 am | News | CommentsCameras fitted with a new sensor will soon be able to take clear and sharp photos in dim conditions, thanks to a new image sensor invented at Nanyang Technological University. The new sensor made from graphene, is believed to be the first to be able to detect broad spectrum light, from the visible to mid-infrared, with high photoresponse or sensitivity.
Diamonds, nanotubes find common ground in graphene
May 28, 2013 11:45 am | News | CommentsWhat may be the ultimate heat sink is only possible because of yet another astounding capability of graphene. The one-atom-thick form of carbon can act as a go-between that allows vertically aligned carbon nanotubes to grow on nearly anything. That includes diamonds. A diamond film/graphene/nanotube structure was one result of new research carried out by scientists at Rice University and the Honda Research Institute USA.
New technique advances carbon-fiber composites
May 20, 2013 7:31 am | by Jennifer Chu, MIT News Office | News | CommentsThese days, aerospace engineering is all about the light stuff. Advanced carbon-fiber composites have been used in recent years to lighten planes’ loads. For the next generation of commercial jets, researchers are looking to even stronger and lighter materials, such as composites made with carbon fibers coated with carbon nanotubes. However, a significant hurdle to achieving such composites has existed, until now.
Stacking 2D materials produces surprising results
May 17, 2013 7:46 am | by David L. Chandler, MIT News Office | News | CommentsGraphene has dazzled scientists ever since its discovery more than a decade ago. But one long-sought goal has proved elusive: how to engineer into graphene a property called a band gap, which would be necessary to use the material to make transistors and other electronic devices. New findings by Massachusetts Institute of Technology researchers are a major step toward making graphene with this coveted property.
Add boron for better batteries
May 16, 2013 2:20 pm | News | CommentsFrustration led to revelation when Rice University scientists determined how graphene might be made useful for high-capacity batteries. Calculations by the Rice laboratory of theoretical physicist Boris Yakobson found a graphene-boron anode should be able to hold a lot of lithium and perform at a proper voltage for use in lithium-ion batteries.
Scientists discover new uses for tiny carbon nanotubes
May 15, 2013 7:25 am | News | CommentsThe atom-sized world of carbon nanotubes holds great promise for a future demanding smaller and faster electronic components. The challenge has been figuring out how to incorporate all of these nanotubes' great properties into useful electronic devices. A new discovery by four scientists at the University of California, Riverside has brought us closer to the goal.
Graphene joins the race to redefine the ampere
May 13, 2013 10:00 am | News | CommentsA new joint innovation by the National Physical Laboratory and the University of Cambridge could pave the way for redefining the ampere in terms of fundamental constants of physics. The world's first graphene single-electron pump provides the speed of electron flow needed to create a new standard for electrical current based on electron charge.
New magnetic graphene may revolutionize electronics
May 10, 2013 12:44 pm | News | CommentsScientists already know that graphene has extraordinary conductive, mechanical, and optical properties. Now it is possible to give it one more property: magnetism. Researchers in Spain have used a technique that involves growing a precise graphene film over a ruthenium single crystal inside an ultra high vacuum chamber where organic semiconducting molecules are evaporated on the graphene surface.
Researchers use graphene quantum dots to detect humidity, pressure
May 8, 2013 3:04 pm | News | CommentsThe latest research from a Kansas State University chemical engineer may help improve humidity and pressure sensors, particularly those used in outer space. A research team is using graphene quantum dots to improve sensing devices in a two-fold project. The first part involves producing the graphene quantum dots. The second part of the project involves incorporating these quantum dots into electron-tunneling based sensing devices.
Engineers fine-tune the sensitivity of nano-chemical sensor
May 8, 2013 1:42 pm | News | CommentsResearchers in Illinois have discovered a technique for controlling the sensitivity of graphene chemical sensors. The sensors, made of an insulating base coated with a graphene sheet are already so sensitive that they can detect an individual molecule of gas. But manipulating the chemical properties of the insulating layer, without altering the graphene layer, may yet improve their ability to detect gases.
Engineers manipulate a buckyball by inserting a single water molecule
May 6, 2013 10:04 am | News | CommentsResearchers have developed a technique to isolate a single water molecule inside a buckyball, or C60, and to drive motion of the so-called “big” nonpolar ball through the encapsulated “small” polar H2O molecule, a controlling transport mechanism in a nanochannel under an external electric field. They expect this method will lead to an array of new applications.
Nanomaterial toxicity study sets stage for policies to address health risks
May 6, 2013 7:41 am | News | CommentsFor the first time, researchers from institutions around the country have conducted an identical series of toxicology tests evaluating lung-related health impacts associated with widely used engineered nanomaterials (ENMs). The study provides comparable health risk data from multiple laboratories, which should help regulators develop policies to protect workers and consumers who come into contact with ENMs.
"Going negative" pays for nanotubes
May 3, 2013 9:17 am | News | CommentsA Rice University laboratory’s cagey strategy turns negatively charged carbon nanotubes into liquid crystals that could enhance the creation of fibers and films. The latest step toward making macromaterials out of microscopic nanotubes depends on cage-like crown ethers that capture potassium cations.
Researchers propose new old way to purify carbon nanotubes
May 1, 2013 11:46 am | News | CommentsAn old, somewhat passé, trick used to purify protein samples based on their affinity for water has found new fans at NIST, where materials scientists are using it to divvy up solutions of carbon nanotubes, separating the metallic nanotubes from semiconductors. They say it's a fast, easy, and cheap way to produce high-purity samples of carbon nanotubes for use in nanoscale electronics and many other applications.
Graphene layers reduce wear, friction on sliding steel surfaces
April 26, 2013 8:48 am | News | CommentsSometimes, all it takes is an extremely small amount of material to make a big difference. Scientists at Argonne National Laboratory have recently discovered that they could substitute one-atom-thick graphene layers for oil-based lubricants on sliding steel surfaces, enabling a dramatic reduction in the amount of wear and friction.
Nanowires grown on graphene have surprising structure
April 23, 2013 7:54 am | News | CommentsWhen a team of University of Illinois engineers set out to grow nanowires of a compound semiconductor on top of a sheet of graphene, they did not expect to discover a new paradigm of epitaxy. The self-assembled wires have a core of one composition and an outer layer of another, a desired trait for many advanced electronics applications.
Spray-on coating combines carbon nanotubes with ceramic
April 17, 2013 2:55 pm | News | CommentsResearchers from NIST and Kansas State University have demonstrated a spray-on mixture of carbon nanotubes and ceramic that has unprecedented ability to resist damage while absorbing laser light. The new material improves on NIST's earlier version of a spray-on nanotube coating for optical power detectors and has already attracted industry interest.
The many uses of nanowires and nanotubes
April 11, 2013 10:18 am | by David L. Chandler, MIT News Office | News | CommentsNanowires and nanotubes have become hot materials in recent years. They exist in many forms—made of metals, semiconductors, insulators, and organic compounds—and are being studied for use in electronics, energy conversion, optics and chemical sensing, among other fields.
ORNL microscopy uncovers “dancing” silicon atoms in graphene
April 3, 2013 4:17 pm | News | CommentsJumping silicon atoms are the stars of an atomic scale ballet featured in a new Nature Communications study from the U.S. Department of Energy(DOE)'s Oak Ridge National Laboratory (ORNL). The ORNL research team documented the atoms' unique behavior by first trapping groups of silicon atoms, known as clusters, in a single-atom-thick sheet of carbon called graphene.
Even graphene has weak spots
March 29, 2013 7:51 am | News | CommentsGraphene has become famous for its extraordinary strength. But less-than-perfect sheets of the material show unexpected weakness, according to researchers at Rice University and Tsinghua University. The kryptonite to this Superman of materials is in the form of a seven-atom ring that inevitably occurs at the junctions of grain boundaries in graphene, where the regular array of hexagonal units is interrupted. At these points, under tension, polycrystalline graphene has about half the strength of pristine samples of the material.
Hybrid ribbons a gift for powerful batteries
March 25, 2013 12:21 pm | by Mike Williams, Rice University | News | CommentsAccording to recent research at Rice University, vanadium oxide and graphene may be a key new set of materials for improving lithium-ion storage. Ribbons created at Rice from these two materials are thousands of times thinner than a sheet of paper, yet have potential that far outweighs current materials for their ability to charge and discharge very quickly. Initial capacity remains at 90% or more after more than 1,000 cycles.
